I need some help getting started on a few wave and sound problems.(adsbygoogle = window.adsbygoogle || []).push({});

1.)A closed organ pipe has a fifth harmonic frequency of 1230Hz at 20 degrees Celcius

a) What is the length of the organ tube?

b) What is the first harmonic of the pipe?

c) If one end of the pipe were opened, what would be the first harmonic?

2.) Consider a sound intensity of 16 x 10 ^-8 W/m^2. At how many times the original distance would the intensity level decrease by 12 db?

3.) What is the wavelength (in meters) of a wave whose displacement is given by y=o.5 sin (0.20x + 120t), where x and y are in meters and t in seconds?

Tarzan swings back and forth on a long vine. His friend Jane notices 30 swings in 2.4 minutes.

a) the frequency of the swing is?

b)the vine's length is?

4.) Middle C has a frequency of 262Hz. What is the frequency of C an octave higher?

5.) The distance from the moon to the earth is 3.8 x 10^5 km.

a) How long does it take a light beam to travel this distance?

b) If instead of a vacuum, the space between had air at STP, how long would it take for sound to travel that same distance?

6.)Spock has landed on a newly discovered planet and is instructed to determine its gravitational strength. He constructs a simple pendulum with a length of 700mm and observes 20 swings in one minute and 16.7 seconds. What does he deduce the "acceleration of gravity" to be from this?

Thanks for any help starting these!

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# Homework Help: A few problems on waves that i need help with

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